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CAP401
05-05-2004, 09:22 PM
Could someone give me some info about this? What I mean is I know what prop pitch is and radiator, but I need to know what position should I have each and when. Maybe this list of questions will clarify more:

1) Could I get a list of what angle of prop pitch to use at what altitude? Ex. Use 20% at 2000m, etc.

2) What is the supercharger and when and where should I imploy it?

3) What is the Magneto and when and where should I use that?

4) Could I also maybe get a list of what mixture to use at which altitude? See the first ex. except replace Prop pitch with mixture.

I'm sorry for being such a noob, but there are so many great pilots here that I'm sure could help.

Now I'm still flying FB with the 1.22 patch to let everyone know. Thx in advance.

S!

CAP401
05-05-2004, 09:22 PM
Could someone give me some info about this? What I mean is I know what prop pitch is and radiator, but I need to know what position should I have each and when. Maybe this list of questions will clarify more:

1) Could I get a list of what angle of prop pitch to use at what altitude? Ex. Use 20% at 2000m, etc.

2) What is the supercharger and when and where should I imploy it?

3) What is the Magneto and when and where should I use that?

4) Could I also maybe get a list of what mixture to use at which altitude? See the first ex. except replace Prop pitch with mixture.

I'm sorry for being such a noob, but there are so many great pilots here that I'm sure could help.

Now I'm still flying FB with the 1.22 patch to let everyone know. Thx in advance.

S!

michapma
05-06-2004, 12:38 AM
Hi there,

A couple of your answers are here:

http://people.ee.ethz.ch/~chapman/il2guide/cemguide/intro.htm

Look in the menu for special topics, although not all are finished unfortunately, especially mixture and supercharger.

Prop pitch settings work the same way at all altitudes. If you are flying Allied aircraft, just use the prop control to set the rpm. The higher you go the more you should lean the mixture. You don't need to start until around 3000m in FB; the mixture controls are not very precise. Supercharger stages can also be switched at between 2500m and 3500m. Go by the manifold pressure reading--if you gain MP by switching, then it was correct to switch. Don't forget to reset the controls when you dive/descend!

Cheers

http://www.baseclass.modulweb.dk/69giap/fileadmin/Image_Archive/badges/69giap_badge_chap.jpg (http://giap.webhop.info)

The ongoing IL-2 User's Guide (http://people.ee.ethz.ch/~chapman/il2guide/) | Forgotten Skies (http://www.forgottenskies.com/)
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CAP401
05-06-2004, 04:22 PM
Thx michapma. That article was helpful. Is there anyone else that can help? Consider this a BUMP.

Chuck_Older
05-06-2004, 04:32 PM
http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

Some folks will say that prop pitch is like gears in a car. Disregard that http://ubbxforums.ubi.com/images/smiley/16x16_smiley-very-happy.gif Unless you already understand prop pitch, the analogy is confusing, at best, and wrong at worst (works in the reverse manner as the analogy)

There is a difference in prop pitch between axis and allied planes.

Allied planes' 'prop pitch' is more of a rev limiter type of arrangement, Axis planes all tend to have more of what you would consider 'prop pitch'.

Some points about prop pitch in allied planes- probably don't need full pitch except for full power climbs and takeoff. other times, about 90% is OK, because it allows you to use higher throttle with less heating problems. Very general point, take that with a grain of salt. prop pitch may be a problem when certain damage occurs to the allied plane. Again, very general, just be aware.

Superchargers- are "on". Can't turn them off as in "Mad Max" http://ubbxforums.ubi.com/images/smiley/16x16_smiley-very-happy.gif Some are automatic, most are two speed. P-51, don't even worry. La-5, you'll need speed 2 over 5000m, I beleive. It's in the readme file, I think. A supercharger is a mechanical device run by the engine, to introduce more air into the combustion chambers. The classic design uses an impeller on top of a plenum chamber, driven by a belt run off the crankshaft.

Magneto is part of the electrical system. You can very safely ignore magnetos and mag drop in Il*2:FB http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif


At low altitudes, you can safely use high or max misture settings. At higher altitudes, you must reduce this. You'll see a fine oily brownish/black exhaust trail behind you. At lower altitudes, 120% mixture can give a performance boost.

*****************************
The hillsides ring with, "Free the People",
Or can I hear the echoes from the days of '39?
~ Clash

Athosd
05-06-2004, 07:54 PM
What Chuck_Older said http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

One other thing to note with pitch and mixture - in operations you will normally only use a small part of the full range available.
For instance with prop pitch you'll probably only ever need to go as low as 75% (the 5% notches used in FB are a bit course - if possible put it on a rotary/slider). Mixture steps are 20%; 100% is good most of the time - only need to run it down to 80% when the engine starts smoking and running rough (alt varies by A/C but as noted its ~3500m).
Super charger staging also differs by A/C (for many its auto) - there is a document on one of the FB discs (2?) that gives CEM tips for most types. I trimmed the non essential info out and printed it off so as to have it handy.

Salute

Athos

CAP401
05-06-2004, 09:28 PM
Thx to everyone for their posts. It really helped me with this issue. One more thing though. Right now I'm trying to master the P-40. It's a great fighter and I'm having some real fun with it http://ubbxforums.ubi.com/images/smiley/784.gif. So does anyone have some CEM tips especially for the P-40? What I'm looking for is something like "between such and such altitude have Prop.p at 80%, mixture at 80%, supercharger at stage 2, magneto stage 2, blah, blah, blah". Also, noone really told me what to do with the magnetos. But really your help already has been tremendous. Thx.

S!

Korolov
05-06-2004, 09:32 PM
Magneto's have no real function - they turn off the engine when off, but once you turn them back on and the prop is spinning, the engine starts right up. Switching between less than two magentos will result in a small loss of engine power.

http://www.mechmodels.com/images/newsig1.jpg

CAP401
05-06-2004, 09:38 PM
Thanks Korolov for the fast reply. Now this CEM is starting to make sense. I feel like such a noob! http://ubbxforums.ubi.com/images/smiley/16x16_smiley-sad.gif http://ubbxforums.ubi.com/images/smiley/34.gif http://ubbxforums.ubi.com/images/smiley/35.gif http://ubbxforums.ubi.com/images/smiley/52.gif

Athosd
05-07-2004, 02:25 AM
CAP401 - Below is an extract from FB's flyable aircraft guide (I trimmed out the aircraft commentary bit - just left the performance relevant stuff).

Curtiss P-40
(P-40E, P-40M, P-40 Field Mod)
Engine: 1,200 HP
Take-Off Speed: 160 km/h / 95 kts
Landing Speed: 155 km/h / 85 kts
Combat Engine Setting: 3,000 RPM
Best Cruise: 2,600 RPM
Economy Cruise: 2,500 RPM
Prop Pitch Control: Manual
Mixture Control: Manual
Boost: No
Supercharger: No
Pilot Notes:
Best performance altitude is between 1,000 and 3,500 meters; worst
performance, above 6,000 meters.


As you can see there's no supercharger - hence poorer performance up high - so you don't have to worry about that bit.
Per previous suggestion your mixture should be 100% up to ~3000m - 120% may offer a small boost at low alt (I guess below 1000m). Probably no need to lean the mixture at all when operating in this planes optimum zone - but 80% above 3000m should be good.
As stated a few times here - don't worry about the Magnetos (if you don't even configure a key for them you won't suffer).
Adjust the prop pitch as required to maintain best RPM, ~3000 in combat ; this is not dependant on altitude.
Take off and landing should be done with 100% pitch.
With practice you will be able to judge the revs by the engine sound - and know when to adjust pitch up or down. Like listening to a car engine - if in 4th and it starts to struggle you drop to 3rd; though in FB you increase the pitch %. If the engine note starts climbing too high (eg in a dive) then you need to decrease the pitch %.
In normal operation you may use 80 - 100% pitch, in general anything lower is only going to be required during a prolonged dive.

I hope this helps.

Have fun.

Athos